"The Supreme Court on Wednesdayappeared deeply skepticalabout the constitutionality ofa federal lawthat denies protection to disparaging trademarks. Almost every member of the court indicated that the law was hard to reconcile with the First Amendment.

The court’s decision in the case, concerning an Asian-American dance-rock band called the Slants, will probably also effectively resolve a separate one in favor of the Washington Redskins football team.

The law denies federal trademark protection to messages that may disparage people, living or dead, along with “institutions, beliefs or national symbols.”

Malcolm L. Stewart, a deputy solicitor general, said the trademark law does not bar any speech, as the Slants remain free to continue to use their name. The law “places a reasonable limit on access to a government program rather than a restriction on speech,” he said, and so “does not violate the First Amendment.”

But Justice Elena Kagan said that even government programs may not discriminate based on speakers’ viewpoints.

“The point is that I can say good things about something, but I can’t say bad things about something,” she said of the law. “And I would have thought that that was a fairly classic case of viewpoint discrimination.” Viewpoint discrimination by the government, the Supreme Court has said, is presumptively unconstitutional.

Justice Anthony M. Kennedy said the law interfered with free expression.

“We have a culture in which we have T-shirts and logos and rock bands and so forth that are expressing a point of view,” he said. “They are using the market to express views.”